Transmission operating mechanism



June 18, 1946. E. R PR|CE I 2,402,343

TRANSMISSION OPERATING MECHANISM Filed Dec. 20, 1945 5 Sheets-Sheet l W! M0 lZ? Hi 76 w n i m W e ldffl I519 I56 /52 My M5 M2 [56 Law HIGH v L46 w F 7.117

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June 18, 1946. p c 2,402,343

TRANSMISSION OPERATING MECHANISM Filed Dec. 20, 1943 5 Sheets-Sheet 2 "val/I H4 [NVENTGK H I -5 I E A EL 1?. PIP/c5 June 18, 1946. PRICE 2,402,343

TRANSMISSION OPERATING MECHANISM Filed Dec. 20, 1943 5 Sheets$heet 3 INVENTOE 514 EL 1%. PE/cE June 18, 1946. E. R. PRICE 2,402,343

TRANSMISSION OPERATING MECHANISM Filed Dec. 20, 1943 5 Sheets-Sheet 4 June 18, 1946. E PRICE 2,402,343

v INVENTOE 54/22 5 P/E/QS r ams June 18, 1946 FICE ransmission 'ornita'rnvc MECHANISM Earl R. Price, site. p nd, m, assignor to Bendix Aviation Corporation, South Bend, Ind., a

' icorporationof Delaware ma a- December 20, 1943, Serial No. 514,937

This invention relates in general to gear shifting mechanism and is of particular utility when employed in connection with speed-changing and direction-reversing gearing commonly used in coupling the internal combustion engine of an automotive vehicle or a tank with the driving vehicle wheels or other propelling devices.

One object ofmy invention is to provide power means for operating a two-speed transmission gear mechanism said mechanism being operably associated with a diflerential mechanism of standard construction and mounted adjacent thereto in the power plant of the vehicle. In other words, it is an object of my invention to provide power meansfor operating the so-called two-speed axle mechanism of the day.

Yet another object of my invention is to provide power means for operating a two-speed axle said power means being controlled by an operation of the accelerator and an operation of a manually operated selector valve.

A further object of my invention is to provide power means for operating a two-speed axle mechanism said power means including a spring and vacuum operated double-acting motor the operation -of which i controlled by the operation of a manually operated so-called four -way or double three-way selector valve and the operation of the accelerator of the vehicle in its control of the speed of the engine and the degree o gaseous pressure within the intake manifold of said engine.

One of the important features of my invention is to provide a double-acting pressure differential operated motor for establishing a change speed transmission in one or .the other of two setting said motor being connected with said ZClaims, (c1. vi-+246) e is cooked, when-the vacuum motor is' energizedv 2 1' called double-acting yieldable means which is of such -'a strength that the same is collapsed, that to effect an operation of the axle mechanism said 'operation being effected prior to a neutralizationof the 'axle mechanism which is effected during-the last part of the movement of the power meansconstituting my invention pow'er element of said motor, the cocked yieldable means then functioning, after the gears of the axle mechanism to be meshed are brought to synchronous speeds by controlling the speed of the engine of the vehicle, to expand thereby efl'ecting a new setting of the axle mechanism. Thereis thus (provided what may be termed a three-stage force transmitting means that is meansjhaving three distinct stage of operation in effecting the disengagement and reengagement of the transmission mechanism.

Other objects of'the invention and desirable details'of construction will become apparent from the detailed description of certain embodiments of the invention described in the specification to follow and disclosed in the accompanying drawings in which:

Figure 1 is a diagrammatic view disclosing the preferred embodiment of my invention serving to operate a so-called two-speed rear axle of an automotive vehicle;

Figure 2 is a schematic view principal elements of the transmission operating and disclosed in Figure 1;

Figure 3 is a view disclosing a portion of the pressure differential operated motor of that embodiment of my invention disclosed in Figure 1 together with the double-acting yieldable means interconnecting said motor with the transmission transmission by means including a so-called douable-acting yieldable means which is energized, that is cooked, during the first half of the gear shifting movement of the power element of said motor and is then operative. after said power element has completed its gear shifting movement to neutralize the transmission, to establish the transmission in gear. Yet another object of my invention is to provide power means for operating the so-called twospeed axle of an automotive vehicle said power means including a double-acting vacuum motor comprising a casing member detachably secured to the casing of'the two-speed axle and further comprising a power element operably connected, to a shift fork of the axle mechanism. The force transmitting means interconnecting the mechanism to be operated;

Figure 4 is a side view of the double-acting torsion spring constituting the aforementioned yieldable means, said spring being shown in combination with two crank members;

Figures 5, 6 and '7 disclose the aforementioned torsion spring and cranks in their three diflerent operative positions;

Figure 8 is a sectional view of the double threeway selector valve of my invention, said view being taken on theline 8-8 of Figure 9;

Figure 9 is a sectional view of said valve taken on the line 9-9 of Figure 8;

Figure 10 is a sectional view, taken on the line Ill-l0 of Figure 11, of another embodiment of my invention this view disclosing a double-act ing pressure difierential operated motor mounted on the casing of a two-speed axle mechanism,

disclosing the the power element of said motor being connected to a shift fork of said axle mechanism by a dou- I able mounting. It is to be understood however that my invention is not necessarily limited to means for operating a two-speed axle; for the double-acting motor I2 of my invention may also be used to operate any multi-speed transmission mechanism to establish one or the other of two settings thereof.

- the vacuum conduit 84 The motor I2 comprises a double-ended casing I4, Figure 2, and a piston that is power element I 8 the latter being connected to the axle mechanism by force transmitting means which constitutes an important feature of my invention. As disclosed in Figures 3 to 7 inclusive this force transmitting means includes a rod I8 fixedly connected to the piston of the motor and projecting through one end of said'motor. As disclosed in Figure 3 this rod I8 is adjustably connected to a pin 28 which is pivotally connected at its bifurcated end to a crank 22. This crank i enlarged at one of its ends, said enlargement, indicated by the reference numeral 24, being somewhat heart shaped in outline. Another crank 28 is pivotally connected to the crank 22 by a pin 28 and a torsion spring 38, sleeved over said pin and interposed between one face of the crank 22 and a washer 32, is secured in place by a nut 34. A tab 38 extends from one end of the crank 28 said tab being contactable which one or the other of stops 38 and 48 mounted on and extending from the casing of the two-speed axle.

Ends 42 and 44 of the torsion spring 88 are spaced apart and extend downwardly; and between said endsor prongs there extends a pin 48 which is fixedly secured to and extends from the heart shaped end portion 24 of the crank 22. A pin 48, fixedly secured to and extending from the crank 28, extends through an arcuate slot in the aforementioned heart shaped end portion 24 of the crank 22; and this pin 48 also lies between the prongs 42 and 44. Completing the description of the force transmitting means interconnecting the power element of the motor [2 and the two-speed axle mechanism the crank 28 is detachably but non-rotatably mounted, by means including a nut 58, upon one end of a'shaft 52 said shaft being connected at one of its ends to the transmission mechanism of the two-speed axle. c

- As disclosed in Figure 2 the two compartments 54 and 58 of the double-acting motor I2 are connected with a so-called double three-way selecnism'of my invention in which case the intake manifold of the engine is directly connected to the control valve 58 by a single conduit; the aforementioned check valve I4 is however included in the latter conduit. 4

Referring now to Figures 8 and 9 disclosing the details of the double-acting three-way selector valve 58 said valve consists of two members I8 and I8. The member I8, which is preferably of steel, is bored to provide three spaced openings 88, 82 and 84 and one end of each of said openings or bores is preferably threaded to receive a nipple, Figure 2. These nipples, which are indicatedby the reference numerals 88, 88 and 88, extend through the instrument panel of the vehicle and constitutes means for mounting the control valve in position. As disclosed in Figure 2 is connected to the nipple 88 and the nipples 88 and. are-connected respectively to the aforementioned conduits 88 and 82. The remaining valve member I8 consists in the main of a half disk member 82', preferably ofrubber or equivalent material, mounted on a relatively thin steel plate 84 of the same outline. The upper edge of the disk member 82 is provided with an arcuate recess 88 and the base portion of said valve member is shaped to provide two recesses I88 and I82 each of which is shaped to ill; around a portion of a pin I84 flxedlymounted in and extending from the inner face of the valve member I8. The valve member I8, consisting pf the members 82 and 84, is non-rotatably mounted upon a shaft member I88 which extends through the valve memberJB; and said shaft member also extends through the instrument panel of the car and a cup-shaped cover member I88 which is friction fitted to and constitutes a cover or housing for both valve nembers. This cover member I88 also constitutes a housing for suitable air cleaner material such as steel wool II8. A crank II2, which may be termed a selector lever is non-rotatably mounted on the'shaft I88 and serves as the means by which the driver rotates the valve member 58 gize the motor I2. 4

Briefly describing now the operation of the control valve 58 when the driver of the car wishes to to selectively enerestablish the two-speed axle mechanism .in its 7 low gear setting he rotates the :valve operating indicated by the'word low tor valve 58 by conduits 88 and 82, and a conduit omitted from the transmission operating mechaselectorlever I I2 clockwise to its low gear position in Figure 2; and by this operation the valve member I8 rotated clockwise, Figure 9, to complete the air transmitting connection between the vacuum tank 88 and the compartment 58 of the motor I2 by the conduit 84, nipple 88, opening 88 in the valve member I8, .the recess 88 in the member 82, the opening 84 in the valve member I8, the nipple 88, and the conduit 82. This operation of the control valve also serves to vent the remaining motor compartment 54 to'the atmosphere via the conduit 82, the nipple 98, the opening 82 in the valve member I8, a compartment I I4 in the valve member I8, openings I IS in a plate H8 which maintains the steel wool in position, and openings I28 in the end wall of the cover member I88. In this operation of the control valve 58 the valve member I8 is rotated until'the pin I84 registers with the recess I82, Figure 9, said pin therefore acting as a stop to insure a, registering of the recess 88 with the openings 88 and 84.

Now inasmuch as by this operation the compartments 58 and 54.01? the motor are partially evacuated and vented to the atmosphere respectively it follows that the piston II of said motor oases scribed in detail it follows that it is unnecessary to describe in detail the high gear operation of said valve and motor; for the latter operationsare, oi course, just .the reverse so to speak of the above described low gear operation. In this high gear operation of the mechanism thelever H2 is moved counter-clockwise to its high gear position thereby rotating the valvemember 18, Figure 9, to register the stop pin I04 in the recess I06. The compartments 54 and 56 are then connected respectively to the source of vacuum and to theatmosphere whereupon the motor is energized to establish the two-speed axle inits high gear setting.

Describing now the complete operation of the mechanism constituting my invention of which toward its high gear position after the spring 26 is cocked and this movement, that is the last half 01' the piston movement, results in a demeshthe accelerator I22 of the vehicle constitutes a part, it will be assumed that the vehicle is at a standstill with the engine idling and that the twospeed axle mechanism is established in its low gear setting. The piston l6 of the motor I2 is then in the position disclosed in Figure 2. Incidentally the multispeed transmission I24, Figure 1, which constitutes a part of the powerplant of most vehicles of the day, is at this time probably establislied in a relatively low gear ratio setting.

' The driver of the vehicle will then depress the accelerator and engage the friction clutch to get the vehicle under way however if the power plant includes a fluid coupling, then an operation of the friction clutch may be dispensed with. Now when the desired vehicle speed is reached in the low desired.

ing of the gears of the axle jmech'anism to neu-.

tralize said mechanism. The cranks 2'2 and 26 then assume the relative positions disclosed in Flgurefi, the tab '26 being located half way or approximately half way between the stops 26 and 46. In this operation the piston l6 bottoms in the cylinder II that is said piston moves until it abuts an end wall of the cylinder casing.

Now when-the speed of the gears to be meshed become equal or substantially so, that is when the same are synchronized by the slowing down I of the driving gear of the axle mechanism, then said gears are meshed to establish the axle mechanism in its high gear setting; and with this operation the cranks 22 and 26 assume the relative positions disclosed in. Figure, 7 the tab 36 moving into contact with th stop l0..,This gear meshing operation is of course eflected by the expansion of the torsion spring 26. The axle mechanism having been established in its high gear setting by operating the control valve 66 and releasing the accelerator the driver will then de-' press the accelerator to either maintain the' existing speed or the vehicle or increase the speed as When the driver mechanism in its low gear setting for example when he desires to quickly pass a car on the road or maintain the car speed when climbing a hill,

he moves the selector lever to its'low gear posi-l tion marked "low" in Figure 2' andthen successively fully .releases and then after a short period of time depresses the accelerator. Describing this operation when the selector lever is moved to its low gear position and the accelerator is released to reverse the engine torque and createa source of vacuum in the intake manifold, then the motor I: is again energized and the aforementioned operation of the force transmitgear setting of the two-speed axle the driver will effect the high gear setting of said axle by releasing the accelerator and moving the selector lever H2 to its high gear setting.- The compartments 54 and 56 of the motor l2 are then connected to.

the source of vacuum and the atmosphere respectively whereupon said motor is energized. Now one of the important features of my invention should be described at this juncture;- .that is the operation of the force transmitting means interconnecting the motor l2 with the two-speed axle and operation of said force transmitting means in conjunction with an operation of, the internal combustion engine which drives the driving gear member of the axle mechanism. Continuing now the description of the operation of establishing the two-speed axle mechanism in its high gear setting, which description brings out this important feature of my invention, when the motor I2 is energized the first half or approximately the first half of the movement of the piston l6 will serve to compress or cook the torsion spring 36; and this operation is efiected'by virtue of the fact that said spring is of such a strength as to compress before the gears of the two-speed axle are demeshed. This operation is effected despite the release of the accelerator to reverse the torque of the engine and lighten the load upon the driving gear of the axle mechanism. With this spring compressing operation the cranks 22 and 26 as-' sume the relative positions disclosed in Figure 5, the tab 36 remaining in contact with the stop 36. The piston l6 of course continues its movement tin means interconnecting the piston l6 and the axle mechanism isrepeated. The first half of the movement of the piston cooks the spring 3.0 and the last half of said movement serves to neutralize the axle' mechanism, both of these operations, as with the above described high gear operation of the motor,.being effected before thegears of the axle mechanism are brought to synchronous speeds and while the accelerator is in its released position to reverse the engine torque.

This gear synchronizing operation is efiected by depressing the accelerator thereby speeding. up

the engine and the driving gearof the axle mechanism connected thereto; When the driving gear reaches its so-called synchronous speed then the gears of the axle mechanism are meshed and said mechanism is established in its low gear set.-

tinz; and as with the above described high gear operation of the axle mechanism this operation is efiected by the expansion of. the torsion spring 30. the cranks 22 and 26 again assuming the relativ positions disclosed in Figure 5 the tab 36 contacting the stop 38.

There is thus provided,.bythe transmission operating mechanism disclosed in Figures 1 to 9 inclusive, 9. very simple, effective and easily serviced mechanism. With this transmission operating mechanism there are but'two controls to be operated by the driverthatis the'accelerator of the car and the selector. valve 56. The vacuum storage tank 66 may of course be omitted from the mechanism disclosed in Figure 1 however to make the mechanism absolutely fool proof it is desires to establish the axle described indetail above.

best to leave said tank, in the system; for said tank would be necessary, in the system if the driver carelessly released tiiaccelerator then immediately depressed t same to destroy the vacuum in the intake man fold'before the'operations of.

cooking the spring and neutralizing the transmission had been completed. 4

There ladisclosedinflgure's" and 11 another embodiment of my invention wherein a. double- ,-acting pressure diflerential operated motor I26 is directly mounted on the casing of the two-speed f axle mechanism. -As disclosed. in Figure 10 the motor I26 comprises a cup-shaped casing member I26 detachably secured, by bolts I26, to a disklike member I36 projecting from a cap portion I62 of the axle housing and to a motor casing member I64 the central portion of which projects inwardly to forms. tubular member I36. The

bolts I 26 also extend through a flange I36 extending from a portion I46 of the casing of the axle housing. The power element,that is the piston I42 of the motor I26 is mounted upon '9. connect-.

Figure 10, that against the stop I62. The

shift fork I46 is by this operation moved to a position midway between the stops I46 and I66.

' -It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and though said invention has been described in connection with a preferred embodiment and a modification thereing rod I44 extending within the aforementioned 1,

tubular portion I36 of the motor casing. The two-speed axle mechanism, not shown, is actuated, to establish said mechanism in one. or the other of its two gear ratio settings, by a shift 1 fork I46 which is reciprocated back and forth betweenstops I46'and I56 by the'operation'of'the motor I26. .One end of the shift fork is cham-' fered at I62 and I64 on its end faces to provide cam surfaces which move into contact with the tapered ends of the stops I46 and I66 and this construction provides a means for limiting the degree of shift movement of the fork;

Describing now the connection between the shift fork I46 and the piston I 42 a tubular member I66 is fixedly secured to the end or hub portion of said fork and a tubular member I66,

fixedly secured to the member I66, is reciprocably -mounted within bearings I66 and I62 mounted within recesses in the tubular member I36. Thrust members I64 and I66, sleeved over the rod I44 between snap rings I68 and I16, are spaced apart by a compression spring I12. The

thrust member I66 is forced by the spring I12 into abutment with one end face of the member I66 and the thrust member- I64 is forced, that is biased by the spring I12 into abutment with the snap ring I embedded within the member I66. The snap rings I66 and I16 are embedded within the rod I44.

Conduits I16 and I16, Figure 10, each connected with one of the two compartments of the motor I26, are connected with adouble threeway control valve duplicating the control valve disclosed in Figures 8 and 9 and which has been As to the operation of the axle operating power means disclosed in Figures 10 and 11 the same need not be described in detail inasmuch as said'operation duplicates the operation of the mechanism disclosed in Figure 1 which operation has been described in detail above. Sufllce it to say that in effecting a low gear setting of the axle mechanism the piston I42 first moves from a position in contact with a stop I 66 secured to the casing member I34 to a position midway between said stop and a stop I62 secured to the casing member I26. The spring I12 is compressed or cocked during this piston movement. The second half of movement of the piston I 42 then effects the den'eshing that is transmission neutralizing operation of the axle mechanism said piston moving. to the position disclosed in of it will be apparent that various changes may bemade in the form, construction, and arrange-- ment of parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the forms herelnbefore described beingmei'ely certain embodiments.

'- I claim: x

1.'In an automotive vehicle provided with a multi-speed rear axle including a casing member and a reciprocable shift fork; means for operating said multi-speed rear aide to establish the same in either a high gear setting or a low gear setting, power means for moving said multi-speed axle operating means in one or the other of two directions to effect the aforementioned operation of the rear axle mechanism'said bower means comprising a double-acting double-ended vacuum operated motor comprising two casing parts each part provided with an outwardly extending flange said flanges being secured together. and to a part of the aforementioned casing of the multi-speed rear axle, said motor further pomprising a reciprocable power element, force transmitting means interconnecting said power element with the aforementioned reciprocable shift fork said force transmitting means including a hollow rod secured to the shift fork, a rod secured to the power element and housed within said hollow rod and means including yieldable means interposed between and constituting the connection between said rods, said power means further including a selector valve for controlling the operation of said motor.

2. In an automotive vehicle provided with a power plant including an internal combustion engine, an accelerator for in part controlling the operation of said engine and a change-speed transmission; means "for operating the said transmission to establish the same in either av high gear setting or a low gear setting, power means, operative in three distinct stages, for moving said transmission operating means in one direction or the other of two directions to effect the aforementioned operation of the transmission said power means comprising a doubleacting pressure differential operated motor including a cylinder and a power element, force transmitting means, including a torsion spring of a certain strength, interconnecting said power element with the aforementioned transmission operating means, and a double threeway selector valve for controlling the operation of said motor; the parts of said power means being so constructed and arranged, and so operative in conjunction with an operation of the internal combustion engine, that to effect the low gear setting of the transmission the driver places the valve in one of its settings. and releases the accelerator whereupon said motor is energized the first half of the movement oi! the power element of said motor, that is the first stage of operation of the power means. serving 5 to cock said torsion spring and the second half of the movement of said power element, that is the second stage of operation of the power means, serving to neutralize the transmission,

the cocked torsion spring being then operative I by its expansion, and after the accelerator is power means.

EARL R. PRICE. 

